The present invention relates to the field of products for treating contact lenses. More particularly, the invention relates to an improved process wherein contact lenses can be cleaned and disinfected with a single product containing one or more polycarboxylates, polysulfonates or polyphosphates. It has been found that these agents effectively remove deposits of proteins and other materials from contact lenses.
Products for treating contact lenses have generally been classified based on the intended use or function of the products. Most products have been classified as either cleaners or disinfectants. However, there are also a number of associated products which can be generally classified as rewetting drops or conditioning solutions. Although there have been attempts to accomplish two or more functions with a single product, such attempts have generally had limited success, because combining the components required to perform multiple functions in a single product tends to reduce the effectiveness of those components. For example, combining surfactants commonly used to clean contact lenses with antimicrobial agents commonly used to disinfect contact lenses may reduce the activity of one or both of these agents. Thus, from a purely scientific standpoint, the combining of two or more functions in a single product has been discouraged.
The perspective of the patient is much different from that of the scientist. The primary concerns of the patient are typically effectiveness and convenience. The latter concern is particularly important among wearers of disposable contact lenses, who tend to be highly motivated toward convenience. The emphasis that patients place on convenience has led to a rapid rise in the popularity of disposable contact lenses capable of supporting either daily or extended wear. Depending on the planned replacement and wearing schedules, these lenses are most commonly cleaned and disinfected daily, and occasionally weekly or biweekly. The result is that many convenience-driven patients who originally sought relief from the rigors of lens care are being fitted with lenses that require daily, albeit less rigorous, care. Such patients place a premium on products that are simple and straightforward to use. By their very nature, frequent replacement lenses worn for daily wear are presumed to require the use of fewer or milder cleaning products. Thus, both patient preference for convenience and the fitting of frequent replacement lenses for daily wear has created a desire for easy-to-use disinfectants that can also be used to clean, soak and rinse lenses.
If the care of the patients' contact lenses becomes too complicated, the patients may fail to comply with the cleaning and disinfection instructions provided by their physicians. Such non-compliance is a major concern of ophthalmologists and optometrists. Repeated failures to clean and/or disinfect contact lenses properly can lead to serious vision problems, such as corneal abrasions, infections, inflammation of the conjunctiva, and so on.
The use of a disinfecting solution to also clean contact lenses has been proposed previously. However, such disinfecting solutions have typically included one or more surfactants as the active cleaning component. A product of this type is currently marketed by Bausch & Lomb as ReNu.RTM. Multi-Purpose Solution.
In view of the foregoing circumstances, there is a need for improved products and processes for cleaning and disinfecting contact lenses in an efficacious but convenient manner.